It is known to use a ballscrew actuator to control the position of a flight control surface in order to “trim” an aircraft's position during flight. The actuator is used to provide a set position of a flight control surface to account for differential load distributions acting on the aircraft due to aerodynamic forces that may undesirably alter the aircraft's position.
It is also known to use a no-back device to prevent the actuator from being back-driven by the aerodynamic forces acting on the flight control surface, which could place the aircraft out of “trim”. Such a no-back device is disclosed in U.S. Pat. No. 6,109,415. The no-back device disclosed therein provides a flange fixed to a screw of the ballscrew disposed between two sets of braking members. When an aerodynamic load is applied to the flight control surface, the screw is loaded in either compression or tension, depending on the direction of the aerodynamic load. The loading causes the flange to shift into contact with one of the two braking members, which then acts to prevent rotation of the screw. The maximum distance that the flange can travel until it is engaged in contact with one of the braking members is known as the “backlash” associated with the no-back device. It may be necessary to adjust the backlash of the no-back device due to operational requirements and/or to account for wear in the device (e.g. wearing of the braking materials over time may increase the backlash). The present disclosure seeks to provide an improved no-back device that allows for a more convenient method for adjusting the backlash associated therewith.